POSTED
8 FEB 2001 Years after it was supposedly vanquished, mad cow disease,
the brain infection that kills cows and some people who eat them, is on
a comeback. The disease has spread widely in Europe, and there are danger
signs in the United States, where it's never appeared.

Mad cow disease
is one of several fatal brain diseases called transmissible spongiform
encephalopathies, or TSEs. (Want The Why Files guide
to mad cow lingo?)

The jargon says
it all: These infectious diseases shoot the brain full of holes, making
it look like a sponge.

The
TSEs were once considered unlikely to infect other species, but some seem
to move rather easily among animals. Most glaringly, many scientists believe
people can get vCJD (variant Creutzfeldt-Jakob disease) from eating mad
cows. The awkward name reflects the similarity to Creutzfeldt-Jakob disease
(CJD), a deadly brain illness that strikes about one person per million
per year, due to genetic or unknown causes.

While CJD mainly
afflicts the elderly, vCJD appears among younger people, almost certainly
from eating mad cow meat. The gruesome death starts with mood
swings, numbness and uncontrolled body movements. Eventually the mind
is destroyed, somewhat like Alzheimer's, another brain-wrecking disease.

The newer variety of CJD usually kills in about 18 months after symptoms appear, compared to four to six months for regular CJD. There is no treatment and both diseases are uniformly fatal.

Mad
with concern
The first known TSE appeared in sheep, but now people, cows, elk, deer,
mink, rats, mice, hamsters and possibly monkeys all get various types
of the disease.

Although neither
mad cow nor vCJD has been seen in the United States, vigilance and concern
are both mounting.

Drugs
and vaccines, including those given to millions of American children,
have been made with products that could carry mad cow disease, in defiance
of repeated requests from the Food and Drug Administration, the New
York Times reported:

"The nine
vaccines include some regularly given to millions of American children,
including common vaccines to prevent polio, diphtheria and tetanus,"
the paper wrote. "They also include the anthrax vaccine, which the
government requires for soldiers serving in the Persian Gulf."

Federal officials
said the practice was still safe, and that nobody is known to have caught
CJD from vaccine.

On
Feb. 1, the government
banned beef imports from Brazil, which had received cattle from Britain
in the 1980s. The action followed a December ban on all animal protein
imports from Europe, and represented a further tightening of restrictions
to prevent infections in the United States.

At
the end of January, a blunder in a Texas feed mill showed that regulations
on feed are not foolproof. Despite quick corrective action, regulators
and industry officials, to say nothing of food safety activists, were
upset that the mill supplied a Texas feedlot with feed containing parts
of slaughtered cattle -- the exact recipe that distributed mad cow across
the United Kingdom more than 10 years ago.

An
old TSE epidemic continues among deer and elk in Colorado and Wyoming,
exposing hunters, and cattle that graze the same terrain, to disease.
Neither human nor bovine infections have been documented, but the long
incubation of TSEs and their mysterious habits are still causing concern.

The
federal government is expanding its ban on blood donations to include
people who lived for 10 years or more in France, Portugal or Ireland
since 1980. People who lived at least 6 months in Britain are already
on the no-donate list.

European
epidemic The picture in Europe is much more distressing.

More
than 80 Britons are already dead from eating mad-cow meat. Most probably
got infected while their government was assuring the nation that the
fearsome cow disease could not infect people.

Three
people in France have died of vCJD, also presumably contracted from
eating meat from diseased animals.

On
Jan. 31., after the detection of 25 mad cows, Germany announced plans
to slaughter and destroy 400,000 elderly cows, which, due to the long
incubation period, are most prone to the disease. Beef consumption in
Germany plunged 50 percent since November, and 34 countries have banned
German beef imports.

Beef
sales have dropped in Spain, where 12 cows showed characteristic holes
in their brains.

Mad
cow has also appeared in Portugal, Switzerland, The Netherlands, Belgium,
Denmark, Ireland, Luxembourg, Liechtenstein and France (see "Bovine
Spongiform... " in the bibliography).

Messed
up in TexasThe
alarm bells rang in Texas after 1,200 cows were fed protein-rich byproducts
of other cows. Until a few years ago, this was standard practice in the
United States, and was considered a smart way to recycle slaughterhouse
offal -- brains, spinal cords, spleens that wouldn't do too well in the
butcher shop -- unless you love head
cheese.

But exactly this
"like to like" feeding technique lay at the heart of the United Kingdom
epidemic. Long after cows began going mad and dying of a brain-destroying
disease, the government allowed their byproducts to be fed to other cows.

The Texas bovine
blunder was probably caught in time. Purina Mills, Inc., owner of the
mill, said it would buy the 1,200 cattle that ate the questionable feed
and remove them from the food chain, to an undetermined destination.

The FDA
stressed other reasons for believing that the mistake was unlikely to
spark a mad cow outbreak: "The prohibited material was domestic in origin
(therefore not likely to contain infected material because there is no
evidence of BSE in U.S. cattle), fed at a very low level, and fed only
once. The potential risk of BSE to such cattle is therefore exceedingly
low, even if the feed were contaminated."

Could
a feed mill be the source of a deadly bovine epidemic?

That opinion, however,
was not universal. "It is unfortunate that there has been a failure
to comply with FDA regulations," says Judd Aiken, a prion researcher at
the University of Wisconsin-Madison. "The key to the whole thing is that we
stop the feeding of sheep and cattle to cattle."

Four or five years
after the British stopped feeding cattle to cattle, there was, he says,
a "precipitous drop" in the mad cow rate. Every mistake, he warns, sets
back the date for ensuring that the slow-acting disease is removed from
the food chain.

The U.S. cattle
industry proudly says no cases of BSE have been found in this country,
and it aims to keep it that way. "We're not taking any chances. We're very intent
on keeping this disease out of the country," says Rick McCarty, a spokesman
for the National Cattlemen's Beef
Association.